Maxed-Out iMac vs Maxed-Out Mac Mini

[dukee101]

Looking for a powerful desktop Mac. Already have a Thunderbolt Display (TBD) but will gladly sell it and use the money toward the 2012 iMac (and its gorgeous display).

Mac Mini (Late 2012)
2.6 GHz Intel Core i7 Quad-Core
16 GB RAM
1 TB Fusion Drive (optional: 512 GB SSD x 2 RAID 0 setup)
Intel HD Graphics 4000
Apple 27" Thunderbolt Display (already purchased/not part of final price below)
~12,800 GeekBench Score
---
$1,300 (with education discount + 3rd party RAM upgrade)

--vs--

iMac 27" (Late 2012)
3.4 GHz Intel Core i7 Quad-Core
16 GB
1 TB Fusion Drive
NVIDIA GeForce GTX 680MX 2 GB
27" LED / IPS Display
~14,000 GeekBench Score
---
$2,700 (with education discount + 3rd party RAM upgrade)

There's a $1,400 difference between these two machines but that's not a fair comparison. If I buy the iMac, I'll sell my TBD for ~$800, making the difference really closer to $600.

The question then becomes: is the powerful desktop CPU, bleeding-edge GPU, and beautiful new LED display worth an extra $600 over the fully-loaded Mac Mini?

You might also be asking: Why such a stark comparison? Why not get a cheaper iMac? Well, to me, it's only worth comparing apples-to-apples (no pun intended). Why get the i5 iMac that scores a weaker GeekBench than the little i7 Mac Mini? If I could have an i7 at $1,300, I should have one at $2,000... but Apple doesn't offer that. And I've got to get a 27" because that's what I'm used to with my current TBD plus I find the lack of RAM upgradability on the 21.5" preposterous.

Another important thing to note is that very soon, FirmTek will be offering a uniquely fast USB 3 external drive enclosure that's actually faster than Thunderbolt! This makes the internal drive upgradeability of both machines moot. I can just add whatever SSD I want and enjoy its top speed by simply plugging in a USB device.

I don't do any heavy work at all, nor do I ever expect to:

• no photo/video editing
• no gaming
• no hardcore data-crunching

But I do push my system around:

• large media libraries I like to browse very quickly (300 GB of personal photos and videos and 500 GB of music)
• aggressive document work
• typically have 40-60 browser tabs open
• 10-15 documents and spreadsheets open
• 10-12 Mission Control desktops
• tons of Finder windows
• at least 15 little applets running in the background (Menu Bar apps, etc.)
• often only have 5-6 GB free of 16 GB RAM

What does the community think I need?

Footnote: If you were buying the Mac Mini setup from zero, as in you had to include the price of a new TBD (~$960) and keyboard+mouse (~$140), then you'd be at $2,400 for the Mac Mini, which is just $300 less than the iMac. Now for $300 it seems like a no-brainer to just get the iMac, right?